Coaptive surgical sealing tool

ABSTRACT

A coaptive surgical sealing tool may be similar to an ordinary hemostat with long (50, 60, 70 or 80 mm) thin jaws for sliding into the liver parenchyma, without tearing the larger blood vessels. The jaws are spring loaded and are designed for uniform compression, and to avoid closing too quickly. The jaws are capable of sealing a 50, 60, 70 or 80 mm sealing length, in a single bite, although it can also seal shorter lengths as well. The tool can be used with existing RF/bi-polar cautery generators.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 61/706,603, filed Sep. 27, 2012, which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

Removal of part of the liver (hepatic resection) is often performed to remove a tumor. Blood loss is a serious complication associated with this procedure. Multiple surgical techniques and devices have been developed to minimize blood loss and improve outcomes in hepatic resection. Several studies including a 2009 Cochrane Systematic Review of techniques for liver parenchymal transection have examined the efficacy of different methods of liver resection. Based on this review, the clamp-crush technique was favored due to low cost and with newer techniques such as cavitron ultrasound surgical aspirator (CDSA), hydrojet, and radio frequency dissecting sealer (RFDS) showing no improvement in morbidity or blood transfusion in comparison to the clamp-crush technique.

The clamp-crush technique generally involves crushing the liver parenchyma using a hemostatic clamp tool to expose small vessels and biliary radicals, which are then divided and sealed via radio frequency (RF) energy provided to the jaws of the tool. Various tools have been proposed for this purpose. However, challenges remain in providing a coaptive surgical sealing tool offering superior performance and efficiency in a simple and low-cost design. It is an object of the invention to provide an improved coaptive surgical sealing tool

DETAILED DESCRIPTION

A coaptive surgical sealing tool may be similar to an ordinary hemostat with long (50, 60, 70 or 80 mm) thin jaws for sliding into the liver parenchyma, without tearing the larger blood vessels. The jaws are spring loaded and are designed for uniform compression, and to avoid closing too quickly. The jaws are capable of sealing a 50, 60, 70 or 80 mm sealing length, in a single bite, although it can also seal shorter lengths as well. The tool can be used with existing RF/bi-polar cautery generators, including generators the Triad-Covidean Ligasure Generator, the ConMed generator or the Enseal generator. The tool is suitable for open surgery uses, and may also be adapted for laparoscopic surgery. The tool may be provided in different sizes for different caliber of vessels. In view of its simple design, the tool may be supplied at low cost, as either a reusable or single use unit.

In use, the jaws may be closed with a gradual compression process, with a compression spring acting against the closing movement, to prevent tearing of larger blood vessels. The jaws may a slot and/or ridge, to leave a pre-grooved line for transection after the seal has been completed. The tool may reduce parenchymal transection times in excess of 50%. With 50 mm of sealing length is can seal more tissue in one bite than any existing device yet is versatile enough to seal small lengths of tissue.

DESCRIPTION OF THE DRAWING

As shown in FIG. 1, and example of the tool 10 has first and second arms 12 and 14 pivotally connected via a hinge 16. A ringer ring 18 is provided on the back or proximal end of each arm 12, 14. Each arm 12, 14 has a jaw 24 in front or distal of the hinge 16. A spring 26 urges the jaws into an open position. A lock tab 20 may be provided adjacent to each finger ring 18, to allow the jaws 24 to remain clamped or closed, against the force of the spring. The tool 10 according is similar to a hemostat clamp, and consequently benefits from ergonomic design elements of a hemostat clamp. Hence the tool 10 provides ease of use when used in open surgery. Connectors 22 may connect electrodes 30 on the jaws 24 to an RF generator.

The jaws 24 are very thin and easy to slide through the liver parenchyma without disrupting the parenchyma architecture. For example, the jaws may a length AA or 50, 60, 70 or 80 mm, and a width BB of 4, 5, 6 or 7 mm. The spring 26 helps to prevent accidentally closing down on the parenchyma to quickly which prevents parenchymal disruption. The jaws 24 may be straight or curved with a radius R of about 3-10 cm. Typically, the curvature of the jaws, if any, is in the downward direction, i.e., about an axis parallel to the axis of the hinge 16.

The electrodes 30 may extend over the full length of each jaw 24, or only partially over each jaw 24, as shown in FIG. 1. The electrodes 30 may optionally be removable and separately replaceable.

A low cost embodiment of the tool may be provided by modifying a conventional hemostat clamp having long slender jaws, to include the spring 26, the electrodes 30 and connectors 22.

METHOD OF USE

As used for hepatic resection, the surgeon slides the jaws 24 through the liver parenchyma. With the jaws appropriately positioned around a vessel or biliary radical, the jaws 24 are slowly closed via the surgeon squeezing the finger rings 18 towards each other. The electrodes 30 on the inside of the jaws are clamped or pressed onto opposite sides of the vessel. The spring 26 acts against this closing movement, helping to provide a slow and controlled movement. With the tool 10 held momentarily in a fixed position, RF energy is then provided to the electrodes 30, sealing the vessel.

The tool may of course also be used for other surgical procedures on other organs apart from the liver.

Results:

From 2010-2012, a total of 51 patients underwent >30% liver resection for malignant disease. All patients underwent open laparotomy for hepatic resection. The patient sample was diverse. The majority of patients underwent resection for metastatic disease to the liver; 4 gallbladder cancer with radical liver resection; 1 hepatocellular carcinoma; 3 patients had documented cirrhosis. Procedures included: 7 patients were combined colorectal primary and liver resection; 2 patients underwent second resection for recurrence; 7 patients had additional nanoknife procedures at the time of resection. Post-op adverse events within 30 days of surgery included 0 bile leaks; 1 blood transfusion; 1 return to operating room for colon anastomatic leak; no intra-abdominal abscess.

Conclusions: Use of the present tool as described appears to be a safe and effective technique for major hepatic resection with minimal post-operative adverse events. 

The invention claimed is:
 1. A surgical tool comprising: first and second arms, each having a front section and a back section, and with the arms pivotally attached to each other at a pivot connection between the front and back section of each arm; a finger ring on the back section of each arm; a spring between the back sections of the arms, with the spring urging the back sections of the arms away from each other; first and second jaws on the front section of the first and second arms, respectively, with the first and second jaws having a length of 5 to 8 cm; and first and second removable electrodes on the first and second jaws, respectively, wherein the first and second electrodes extend around a circumference of at least end portions of the first and second jaws, respectively.
 2. The surgical tool of claim 1 with the first and second jaws each having a width of 4-7 mm.
 3. The surgical tool of claim 1 with the first and second jaws each having a width of 4-6 mm.
 4. The surgical tool of claim 1 further comprising first and second connectors electrically connected to the first and second electrodes and adapted to connect to an RF generator.
 5. The surgical tool of claim 4 further comprising at least one of a slot and ridge on at least one of the first and second jaws for leaving a pregrooved line for transection after a vessel is sealed by the surgical tool.
 6. A surgical method, comprising: sliding the jaws of a surgical hemostat clamp-type of tool through the liver parenchyma; positioning the jaws around a vessel; overcoming a spring force acting to hold the jaws open; closing the jaws to press removable electrodes extending around the circumference of at least end portions of the jaws onto opposite sides of the vessel; and applying RF energy to the electrodes to seal the vessel.
 7. The method of claim 6 with the jaws having a length of 5 to 8 cm.
 8. The method of claim 6 further comprising leaving a pregrooved line for transection after sealing the vessel.
 9. The surgical tool of claim 5 wherein the at least one of a slot and ridge are on at least one of the first and second electrodes. 